Browsing by Author "Lima, A. S."
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- Acetylcholinesterase Inhibition Activity of Portuguese Thymus Species Essential OilsPublication . Dandlen, S. A.; Miguel, Maria Graça; Duarte, J.; Faleiro, Leonor; Sousa, M. J.; Lima, A. S.; Figueiredo, A. C.; Barroso, J. G.; Pedro, L. G.Thymus species are commonly known in Portugal as thyme and they are currently used as culinary herbs, as well as for ornamental, aromatizing and traditional medicinal purposes. The essential oils isolated from the Portuguese Thymus caespititius (Sect. Micantes), T. camphoratus and T. capitellatus (Sect. Thymus, Subsect. Thymastra), T. carnosus, T. zygis subsp. sylvestris and T. zygis subsp. zygis (Sect. Thymus, Subsect. Thymus) were evaluated for acetylcholinesterase inhibition capacity. A great variability in activity was detected in the assayed essential oils, even among oils isolated from a same species with different geographical origins, such as T. caespititius. T. zygis subsp. zygis essential oil showed the strongest acetylcholinesterase inhibition capacity with an IC50 = 1.1 mu g/ml.
- Antimicrobial activity, cytotoxicity and intracellular growth inhibition of Portuguese Thymus essential oilsPublication . Dandlen, S. A.; Lima, A. S.; Mendes, M. D.; Miguel, Maria Graça; Faleiro, Leonor; Sousa, M. J.; Pedro, L. G.; Barroso, J. G.; Figueiredo, A. C.Thyme essential oils are well recognized by their excellent biological activities and the antimicrobial activity of Portuguese thyme essential oils has been investigated with promising results, particularly against food borne pathogens. In this study the potential antimicrobial activity of the essential oils of five species of Thymus (Lamiaceae), namely Th. caespititius Brot., Th. camphoratus Hoffmanns. & Link, Th. capitellatus Hoffmanns. & Link., Th. carnosus Boiss. and Th. zygis L. was evaluated against Candida albicans, Haemophilus influenza, Helicobacter pylori, Listeria monocytogenes, Salmonella enterica and Streptococcus pneumoniae. H. pylori strains were the most susceptible bacteria, particularly to the essential oils of Th. caespititius (Planalto Central), Th. zygis (Rebordaos) and Th. caespititius (Pico) which minimum inhibitory concentration (MIC) values ranged from 0.05 to 0.08 mg. mL(-1). Th. caespititius essential oil from Planalto Central or its main component, carvacrol significantly (p<0.05) inhibited the intracellular growth of H. pylori, and showed no citotoxicity to the gastric cell line. Our results suggest the potential of this essential oil and its main component as a promising tool as anti-Helicobacter agent potentiating the eradication of this important gastroduodenal pathogen.
- Antioxidant, Anti-5-lipoxygenase and Antiacetylcholinesterase Activities of Essential Oils and Decoction Waters of Some Aromatic PlantsPublication . Albano, Sílvia; Lima, A. S.; Miguel, Maria Graça; Pedro, L. G.; Barroso, J. G.; Figueiredo, A. C.The scavenging of free radicals and superoxide anion, the inhibition of 5-lipoxygenase and the antiacetylcholinesterase activities of essential oils and decoction waters of eight aromatic plants (Dittrichia viscosa, Foeniculum vulgare, Origanum vulgare, Salvia officinalis, Thymbra capitata, Thymus camphoratus, Thymus carnosus and Thymus mastichina) were studied. The essential oils were dominated by 1,8-cineole in S. officinalis (59%), T. mastichina (49%) and T. camphoratus (21%); borneol (20%) in T. carnosus; carvacrol in Thymbra capitata (68%); gamma-terpinene (49%) in O. vulgare; alpha-pinene (26%) in F. vulgare; and trans-nerolidol (8%) + beta-oplopenone (7%) in D. viscosa. O. vulgare decoction waters had the highest amount of phenols (45 +/- 3mg GAE/mL) while F. vulgare only had 5 +/- 0mg GAE/mL. The decoction waters showed higher radical scavenging activity than the essential oils. O. vulgare decoction water showed the best antioxidant activity (IC(50) = 3 +/- 0 mu g/mL), while the most effective essential oils were those of Thymbra capitata (IC(50) = 61 +/- 2 mu g/mL) and O. vulgare (IC(50) = 156 +/- 5 mu g/mL). Thymbra capitata (IC(50) = 6 +/- 0 mu g/mL) decoction water showed the best superoxide anion scavenging activity. F. vulgare decoction water and essential oil revealed the best 5-lipoxygenase inhibition capacity (IC(50) = 27 +/- 1 mu g/mL and IC(50) = 68 +/- 2 mu/mL, respectively). T. mastichina (IC(50) = 46 +/- 4 mu g/mL), S. officinalis (IC(50) = 51 +/- 4 mu g/mL), Thymbra capitata (IC(50) = 52 +/- 1 mu g/mL) and T. camphoratus (IC(50) = 137 +/- 2 mu g/mL) essential oils showed the best antiacetylcholinesterase activity.
- Propolis volatiles characterisation from acaricide-treated and -untreated beehives maintained at Algarve (Portugal)Publication . Miguel, Maria Graça; Nunes, S.; Cruz, C.; Duarte, J.; Antunes, Maria Dulce; Cavaco, A. M.; Mendes, M. D.; Lima, A. S.; Pedro, L. G.; Barroso, J. G.; Figueiredo, A. C.The variability of the volatile profile of 70 propolis samples from acaricide-treated and -untreated beehives maintained at Algarve (Portugal) was evaluated. Propolis samples were collected in three regions of Algarve at three different periods. Cluster analysis based on the propolis volatiles' chemical composition defined two main clusters, not related to the time of year, collection site, altitude, temperature or humidity ranges, and was based mainly on the relative amounts of viridiflorol, n-tricosane and n-nonadecane for cluster I. Cluster II was mainly characterised by the high thymol content, followed by viridiflorol, n-tricosane and n-nonadecane. The presence of higher thymol levels in propolis samples from cluster II may reflect the long use of an acaricide with thymol as main active ingredient. All samples showed an intense rock-rose aroma supported by the presence of characteristic Cistus and labdanum oil volatile components. Given the nowadays frequent propolis household use, volatiles thorough characterisation may assist in its quality assessment.